2007³-2006×2007×2008
=2007×(2007²-2006×2008)
=2007×[2007²-(2007-1)×(2007+1)]
=2007×[2007²-(2007²-1²)]
=2007×(2007²-2007²+1²)
=2007×1
=2007
2007³-2006×2007×2008
=2007×(2007²-2006×2008)
=2007×[2007²-(2007-1)×(2007+1)]
=2007×[2007²-(2007²-1²)]
=2007×(2007²-2007²+1²)
=2007×1
=2007